REGION: Scientists seek rare basking shark sightings

Gentle, 33-foot-long fish listed as 'species of concern'

Despite such occasional mass sightings, the animals have grown
scarce in recent decades. Researchers said thousands were killed in
fishing and eradication programs in the 1900s, and the slow-growing
species never recovered.

Heidi Dewar, a fisheries biologist with NOAA, said that between
1940 and 1970, Canadian fishermen killed the sharks using a device
called a "razor-billed shark slasher" to prevent their entanglement
in salmon gill nets.

"They designed a big knife that they would attach to the front
of boats," she said. "It would ram the animals and cut them in
half."

Between 1924 and 1950, Dewar said, American fishing fleets
caught as many as a thousand of the sharks for their meat, skin,
fins and livers. While Western nations no longer fish for the
animals, there may still be an Asian market for the fins, which can
fetch tens of thousands of dollars each, she said.

"In Asia, I wouldn't be surprised if they're targeted for their
fins, because they're so valuable for shark fin soup," she
said.

The loss of basking sharks in the last century may have caused a
long-term population drop. Scientists believe the animals reproduce
infrequently and bear few pups, leaving them ill-equipped to
recover.

"They replace themselves very slowly, which means that you can't
take many out ... without impacting the population," Dewar
said.

The current population estimate for basking sharks is fewer than
10,000 worldwide, Dewar said. However, she said that's an educated
guess based on a genetic analysis, and that there are no accurate
surveys of the animal.

To fill those data gaps, the scientists seek to mark at least
two more sharks and follow their migrations for a year or more
through tags that transmit data to global positioning system
satellites when the animal surfaces, and after the tag
releases.

Finding the rare sharks is a challenge, so the scientists are
asking members of the public to report any sightings that might
lead them to sharks they can tag.

"If we can get some idea of when and where these things show up,
we might be able to get in the water and get some observations on
them," Ebert said.

The sightings themselves ---- along with records such as photos,
location data and times and dates ---- will help flesh out the
record on basking sharks, Ebert said.

Rod Melchert, captain and owner of San Diego Sportfish, said he
volunteered to watch for the animals, and to take the researchers
to locations where the sharks have been seen.

"They're just a really neat animal, and nobody really knows a
lot about them, so it's just an opportunity to be on the forefront
of the research," Melchert said.